Braking pressure control device for automotive vehicles

Abstract

The present invention relates to a braking pressure control device for automotive vehicles including a regulating valve, composed of a regulating piston (5) and a valve closure member (6), which governs the connection between a pressure-fluid inlet (3) and a pressure-fluid outlet (4). The valve closure member (6) is coupled to a pressure-responsive displaceable control piston (20). The control device also includes a deceleration responsive deflectable inertia member (33). The displacement of the control piston (20) is controlled as a function of the position of the inertia member. In order to simply accomplish an abrupt and temperature-independent locking of the control piston when a deceleration value is exceeded, the inertia member (33) moves into a mechanical latching engagement with the control piston (20).

What is claimed is: 
     
       1. A proportioning braking pressure control device for automotive vehicles said device comprising a housing, a fluid inlet, a fluid outlet, a regulating valve, means including a regulating piston and a valve closure member, a regulating spring acting on said regulating piston, said regulating piston subjected to fluid pressure at said outlet to be urged to seat on said valve closure member adjacent the force of said regulating spring, said regulating piston and said valve closure member thereby coacting with each other to modulate fluid communication between said inlet and said outlet, said valve closure member operatively associated with an inlet pressure responsive control means, including a control piston and a control spring, said control piston progressively displaced against the force of said control spring in response to increasingly control inlet fluid pressure, said valve closure member coupled to said control piston to be displaced away with said control piston to prevent said modulation of fluid communication between said inlet and said outlet; and, an inertia member, support means mounting said inertia member to be shiftable from a gravity biased position to an advanced position when said vehicle experiences a predetermined deceleration rate, latching engagement means operative to stop the displacement of said control piston in at least one axial direction in response to shifting of said inertia member to said advanced position, said latching engagement means includes a locking member progressively displaced with said control piston and a series of latching engagement features on said inertia member and said locking member moved into latching engagement at various displaced positions of said control piston and locking member upon shifting of said inertia member to said advanced position to stop further displacement of said control piston from said displaced position whereat said latching engagement occurs. 
     
     
       2. A braking pressure control device as claimed in claim 1, wherein said engagement features on said inertia member and locking member define a hooking engagement therebetween. 
     
     
       3. A braking pressure control device as claimed in claim 2, wherein said engagement features define multiple engagement points whereby displacement of said piston can be checked in one of a plurality of positions in response to shifting of said inertia member to said advanced position. 
     
     
       4. The braking pressure control deviced as claimed in claim 3, wherein a series of saw teeth are formed in said locking member and a hook is formed on said inertia member adapted to be received into one of said saw tooth, said saw tooth and said hook comprising said latching engagement features. 
     
     
       5. A braking pressure control device as claimed in claim 1, wherein said support means for said inertia member comprises a knife-edge support. 
     
     
       6. A braking pressure control device as claimed in claim 5, further including an abutment on a side of the inertia member opposite to the knife-edge support closely spaced over said side of said inertia member when said inertia member is in said advanced position.